Feeding device for rock drills



1933- G. w. HULSHIZER 1,893,999

FEEDING DEVICE FOR ROCK DRILLS Filed D86. 18 1929 INVENTOR. 4eo1yeIlUfidahz3e-r Wag H15 ATTORNEX Patented Feb. 28, 1933 UNITED STATES PATEN FFICE GEORGE W. HULSHIZER, OF STEWARTSVILEE, NEW JERSEY, ASSIGNOR TO ING-ERSOLL- RAND COMPANY, OF JERSEY CITY, NEW JERSEY, A CORPORATION OF NEW JERSEY FEEDING DEVICE FOR ROCK DRILLS Application filed December 18, 1929. Serial No. 414,953.

This invention relates to rock drills, but more particularly to a feeding device for fluid actuated rock drills of the hammer type.

The objects of the invention are to maintain a suitable pressure on the rock drill for feeding it towards the work in accordance with the penetration of the drill steel into the material being drilled, and to facilitate the operation of withdrawing the drifter from the Work.

Other objects will be in part obvious and in part pointed out hereinafter, and to all of these ends the invention consists of the combination of elements and arrangement of parts substantially as hereinafter described and claimed and illustrated in the accompanying drawing, in which Figure 1 is a longitudinal sectional view of the feeding device constructed in accordance with the practice of the invention and showing the manner in which it may be applied to a rock drill,

Figure 2 is a front elevation of the feeding device, the shell whereby it is supported and of the rock drill,

Figure 3 is a similar view of the rear end of the apparatus shown in Figure 1, and

Figure 4 is a sectional elevation of a detail showing the throttle valve in one if its controlling positions.

Referring to the drawing, A designates a rock drill comprising a cylinder B and front and back heads C and D which are clamped to the cylinder B by means of the usual side rods E. Extending into the front head is a working implement F against which the blows of the hammer piston (not shown) and which the cylinder B is adapted to accommodate, may be delivered.

In accordance with the present invention, means are provided for feeding the drilling apparatus under the influence of pressure fluid. To this end a mounting is provided for the drill A in the form of a feeding cylinder G which is provided with standards H and J arranged respectively at the front end of the cylinder B and the back end of the back head D to support the drill A. The standards H are preferably so arranged that for clamping the front end of the drill to the cylinder and the standards J are disposed on opposite sides of the back head D to which they may be secured by means of a bolt K.

In order to enable the feeding device to be readily applied to existing drill supports, such as the shell L, the cylinder Gris provided on diametrically opposite sides thereof with longitudinally extending ribs 0 which slide in the usual guideways P within the shell L.

At the opposite sides of the shell L are lugs Q, which support one end of rods R extending rearwardly of the shell L. The rear or free ends of the rods R support a cross head S to which is fixedly secured a piston rod T extending into the cylinder G and carrying on its free end a piston head U which is held in spaced relation with respect to the cross head S by a tube V surrounding the piston rod T. The rear end of the piston head U abuts the front end of the tube V and a nut W threaded on the end of the rod T clamps the piston head firmly against the end of the tube V.

Into the rear end of the cylinder G is threaded a plug X which serves as a head for the cylinder and has a suitable bore Y ti iough which the piston rod is adapted to s i e.

The cross head S serves as a housing for a throttle valve Z of the rotary type having a central chamber 7) into which pressure fluid from a suitable source of supply may be constantly admitted. In the wall of the throttle valve Z is a port 0 which may be of such extent that it may simultaneously communicate with a pair of passages (Z and e in the cross head S and the rod T. The passage 6 has an outlet opening f in the tube V and immediately rearwardly of the piston head U, and the passage (5 extends entirely through the rod T to convey pressure fluid to the front end of the cylinder G.

The passage 6)! also serves to convey the exhaust fluid from the front end of the cylinder G, and such exhaust fluid may be conducted from the passage cl by a groove 9 in the periphery of the throttle valve and through an exhaust port it in the cross head the side bolts E may extend therethrough S In order to also enable the supply of pressure fluid to the rock drill A to be controlled by the throttle valve Z, said throttle valve is provided with a port j which is adapted to register with a passage is communicating with a supply connection 0 connected to the back head D of the rock drill.

The operation of the device is as follows: lVith the throttle valve in the open position illustrated in Figure 1, pressure fluid will flow through the port the passage k and the connection 0 into the back head to supp y pressure fluid to the percussive element of the drill A. Vith the throttle valve in this position, pressure fluid will also flow through the port 0 and through the passages cl and 0 into both ends of the cylinder G.

Inasmuch as the area of the front end of the piston head U exceeds the area of the rear end of said piston head, the pressure fluid in the front end of the cylinder G will gradually move the drilling apparatus in the direction of the work.

After the working implement F has penetrated the work to the desired depth, the throttle valve Z may be rotated a partial revolution to move the port 0 into a position where it will only register with the passage 0. The groove 9 will then establish communication between the passage (Z and the exhaust port h, whereupon the pressure fluid from the front end of the cylinder G will be exhausted to the atmosphere. The pressure in the rear end of the cylinder G will then retract the drilling apparatus to its rearmost limiting position in readiness for a succeeding drilling operation.

I claim:

1. In a drill feeding device, the combination of a rock drill and a shell therefor, a feeding cylinder in slidable engagement with the shell, there being means on the cylinder to support the rock drill, means for clamping the first mentioned means to the rock drill, a cross head supported by the shell. a piston in the cylinder, a piston rod for the piston secured to the cross head and having passages therein for conveying pressure fluid to the ends of the cylinder to actuate the cylinder and the rock drill longitudinally of the shell, and a throttle valve in the cross head to control the passages.

2. In a drill feeding device, the combination of a rock drill and a shell having guideways, a feeding cylinder having ribs slidable in the guideways, means integral with the cylinder to support the rock drill, means for clamping the first mentioned means to the rock drill, a cross head, means for connecting the cross head to the shell, a piston in the cylinder, a piston rod connected at one end to the piston and at the other end to the cross head, said rod having passages for conveying pressure fluid to and from the ends of the cylinder, and a throttle valve in the cro$ head to control the passages.

3. In a drill feeding device, the combination of a rock drill and a shell having guideways, a feeding cylinder having ribs slidable in the guideways, standards integral with the cylinder to support the rock drill, means for clamping the rock drill to the standards, a cross head, means for connecting the cross head to the shell, a piston in the cylinder, a piston rod connected at one end to the piston and with the other end to the cross head, said piston rod having passages for conveying pressure fluid to and from the ends of the cylinder, a connection for conveying pressure fluid from the cross head to the rock drill, and a throttle valve in the cross head to control the passages and to control the admission of pressure fluid into the connection.

at. In a drill feeding device, the combination of a rock drill and a shell having guideways, a feeding cylinder having diametrically arranged ribs slidable in the guideways, standards on the shell and spaced along the length thereof to support the rock drill, means for securing an intermediate portion and the rear end of the rock drill to the standards, a piston in the cylinder and being affixed to the shell, and means for introducing pressure fluid into the ends of the cylinder to actuate the cylinder and the rock drill longitudinally of the shell.

In testimony whereof I have signed this specification.

GEORGE WV. HULSHIZER. 

